We don’t know what the beaner was doing with the sign before the tape started. It’s conveniently edited to put the security in the worst light possible.
I only know what I saw. What I saw was the guard stealing the sign and protester trying to get it back when he was sucker punched by the Trump guard.
I recall a teacher at a university stealing a pro-life sign and shoving a pro-life protester and the teacher was fired and convicted of theft and assault.
This appears to be a similar incident.
I can't tell much about the person who posted that video since I can't read Arabic.